Meteoroid, Bolide and Meteorite «Chelyabinsk»

Abstract

This paper presents the brief review of Chelyabinsk group of meteoroid, bolide and meteorite "Chelyabinsk" investigations. Height of the maximum of the main flash of Chelyabinsk bolide is 30 km. Only 1% of meteoroid mass arrived to the Earth surface in the form of meteorites while the most part of meteoroid became dust. During four days the dust had circumnavigated the globe and formed stratospheric dust belt. This new dust belt, located above the Junge aerosol layer, has persisted over at least a three-month period. The mass distribution of found meteorites is lognormal. This shape argues that fragmentation process of initial body happened randomly and in a cascade way. Transparent or translucent mineral filaments firmly linked to the particles were found in the meteoritic dust. In metallic phases of the meteorite mainly Fe-rich compounds exist. Very interesting topics of next research are magnetic properties of Fe-Ni phase, because of cosmic synthesis conditions. Meteoroids like "Chelyabinsk" fall on average once every 30 years. Therefore the problem of "asteroid and comet danger" should be expanded to the problem of "meteoroid, asteroid and comet danger".

The Mechanical Properties of Chelyabinsk LL5 Chondrite Under Compression and Tension

“…There are many light inclusions inside the meteoritic material (Fig. 5a, b), which are apparently a mixture of Fe, Ni metal blebs (Dudorov et al 2016) with some sulphides additions. The size of the light inclusions is ranged from 10 to 100 µm (Fig.…”

“…5c). It has been shown that the light inclusions are metallic phase consisting mainly of Fe and Ni (Dudorov et al 2016). Brittle cracks propagated into Fe, Ni blebs which previously had been fracture free.…”

“…It is well known that fragmentation of the meteorite Chelyabinsk began at an altitude of about 30 km above the Earth's surface (Popova et al 2013;Dudorov et al 2016). The air density at this height can be estimated by the barometric formula (Emmert 2015) and is about g ≈ 0.05 kg/m 3 (Dudorov and Mayer 2014).…”

“…According to Galimov et al (2013), the Chelyabinsk meteorite contains roughly one-third of shock-melted material, which composition is similar to the composition of the major part. Other recent work has focussed on the comparison of Chelyabinsk with other meteorites (Gorkavyi et al 2019;Flynn et al 2018), refinement of its fall trajectory (Buhl and Wimmer 2013), a search of sources of its cosmic origin and discovering new ways to protect people from asteroidal hazards (Dudorov et al 2016;Popova et al 2013;Emel'yanenko et al 2013;Grygorian et al 2013;Borovicka et al 2013). Despite the considerable attention attracted to the Chelyabinsk meteorite, the data about its mechanical properties are not sufficient to date as it usually requires a strong multidisciplinary collaboration of astronomers, mechanicians and material scientists.…”

On the possibility of through passage of asteroid bodies across the Earth’s atmosphere

“…Note that the employed model does not involve the process of SB fragmentation (Barri 2010;Stulov & Titova 2001;Dudorov et al 2015), since the initial dimensions of the SB are taken to be quite significant (from 50 to 200 metres) as well as moderate velocities, when most of the SB remains intact, despite extreme external influences. First of all, maximum resistance to fragmentation is characteristic of iron SBs that is associated with the high homogeneity of their internal structure.…”